Chosen Solution
Hey All! So this is a weird one – recently acquired from recycler a dozen 2018 Airs. All great shape, all power on, all wiped. However, when they attempt Internet Recovery, they sit there forever, and after an hour they overheat and reboot. I have also tried connecting to ethernet, and multiple Internet sources, so I know weak connection is not the problem. These are not locked, but they have the default security utility setting for a 2018 which disallows booting from an external drive, so that is not an option. I have tried wiping in DFU mode, and that did not change anything. Anyone have ideas? I keep thinking GPU issue, but very odd that a dozen machine would have exact same symptoms. Also, look at this picture – the progress bar looks weird. Never seen it like that, and they all look like that. Thanks! John
I somehow missed the fans revving part of this question. But my guess is batteries are toast. I’m not sure where all of them came from, but it would make sense why someone might ditch them en masse if they didn’t know this and figured something bigger was wrong. When a MacBook doesn’t hear from one of the many sensors scattered throughout the device, the SMC assumes the worst and compensated accordingly. It throttles the CPU and revs the fans up to max even if temps are ice cold. It’s an overly concerned mother who hasn’t heard from her kid at exactly the prescribed time. “What if the missing sensor data means everything is on fire?” A bad battery is one of the mail culprits of this behavior (the other is trackpad). So I would wager this is the deal. If the device is being throttled, that also explains the inability to load Internet recovery as well as finish a DFU Restore (or revive). For the record, revive is essentially a reinstall of the firmware, but keeps all existing data on the machine. Restore just wipes the whole thing, even uninitializes the drive. It’s probably timing out because it’s running at colossally slow speeds, but it’s hard to notice that if that’s all you can get. Luckily, the batteries in these are not too hard to replace. You do have to take the logic board out to get at the keyboard connector hiding underneath. But in comparison to a MacBook Pro of the same era, it’s a cakewalk.
